摘要:
The synthesis of both enantiomers of dodecyl rhamnospicamycin 2a and 2b, a rhamnose analogue of the naturally occurring combinatorial library spicamycin 1, are derived from L-rhamnose and methyl alpha-D-mannopyranoside, respectively. The L-(+)-enantiomer 2a containing an L-rhamnose fragment is shown to be highly cytotoxic towards human myeloma cells with an IC50=120 nM, whereas the D-(-)-enantiomer 2b, based on a D-mannose structure, shows no significant cytotoxicity. The analogue 16, in which the nucleotide base fragment has been replaced by a simple methoxy group, has no cytotoxicity. Initial studies towards clarifying the mechanism of anti-cancer action of spicamycin analogues are reported. (C) 1999 Elsevier Science Ltd. All rights reserved.